When President Obama hosts former President George W. Bush at the White House on Thursday to unveil his predecessor’s official portrait, he’ll pay tribute to the man he has blamed lately for everything short of an outbreak of the flesh-eating virus.

The war in Iraq? An unnecessary and costly diversion that was Mr. Bush’s fault, according to Mr. Obama.

The worst recession since World War II? The president says Mr. Bush and the GOP are to blame.

Soaring deficits? Mr. Obama’s mantra is that he inherited the red ink from the Republican.

The Wall Street collapse? See “Bush, George W.”

Loss of America’s prestige in the eyes of the world? Mr. Obama has laid that accusation on Mr. Bush’s doorstep, too.

At a fundraiser in California last week, Mr. Obama used Mr. Bush as his foil to raise more money for his re-election campaign. The president began by criticizing GOP presidential candidate Mitt Romney for planning “bigger tax cuts for the wealthiest Americans,” deep cuts in funding for education and Medicare, and deregulation of the banking and insurance industries.

“But that’s not new,” Mr. Obama told the crowd. “That was tried, remember? The last guy did all this.”

His audience laughed and applauded at the punch line delivered at Mr. Bush’s expense.

Indeed, Mr. Obama is building his re-election campaign on the theme that Mr. Romney would take the nation back to what are characterized as the disastrous policies of the Bush era. In the 2008 presidential race, Mr. Obama also repeatedly warned that a victory for Republican John McCain would be like a third Bush term.

In spite of all this, when “the last guy” visits the White House for the hanging of his portrait, those who know Mr. Bush best say it will be a moment to set aside partisanship and to reflect on the accomplishments of the man and his presidency, and of former first lady Laura Bush. Her portrait will be unveiled, too.

“This event is about portraits, not politics, and President and Mrs. Bush — and many of us who served in their administration — are looking forward to the honor of being back in the White House,” said Karen Hughes, a former top adviser to Mr. Bush who now works as global vice chairwoman of Burson-Marsteller public relations.

Asked whether the meeting will be awkward for Mr. Obama, White House press secretary Jay Carney said, “Not at all.”

“I know the president looks forward to it,” Mr. Carney said. “There are differences without question between his approach and the approach and the policies of his predecessor.”

But he added, “There is a community here with very few members that transcends political and policy differences. There is so much shared experience between [presidents] that there is much to talk about that they hold in common. So there’s not a lot of need to talk about where they differ.”

After Mr. Bush left office in 2009, he pledged, “I’m not going to criticize my successor.” He largely has held to that promise by staying out of the spotlight for the most part of the past four years.

Mr. Bush did criticize Mr. Obama indirectly last month for promoting a tax increase on income of more than $1 million, known as the “Buffett rule,” saying it would hurt small businesses.

The former president this month endorsed Mr. Romney, although the announcement was about as low-key as possible. He told an interviewer, “I’m for Mitt Romney,” just as the doors to his elevator closed as he was preparing to give a speech in Washington.

While Mr. Bush has been restrained in his public remarks about Mr. Obama, his old running mate has shown no such reticence. Former Vice President Dick Cheney has called the Obama administration “an unmitigated disaster.”

As Mr. Bush prepares to watch his portrait unveiled for posterity, the nation’s 43rd president is undoubtedly aware of how it feels to be in Mr. Obama’s shoes.

In June 2004, Mr. Bush played host at the White House for the unveiling of portraits of former President Bill Clinton and former first lady Hillary Rodham Clinton. The event was held four years after Mr. Bush campaigned on the promise to restore “honor and dignity” to the Oval Office — a reference to the Monica Lewinsky scandal that resulted in Mr. Clinton’s impeachment.